1. Field of the Invention
This invention relates to a system for ascertaining the latitude and longitude of an individual or object at a remote location and transmitting information to a base operation using a man-pack or singular portable personnel unit that embodies a cellular telephone network in conjunction with a satellite navigation system, and specifically to a hand-held locating unit that can serve both as a cellular telephone and a portable globular positioning system to provide latitude and longitude information for display at a base unit.
2. Description of the Prior Art
The prior art shows a plethora of systems for locating individual vehicles relative to a central station. Raoux U.S. Pat. No. 4,701,760, issued on Oct. 20, 1987 shows a vehicle monitoring system that uses World Omega Network and a vehicle carried receiver to provide approximate coordinates to a central location. DiLulo et al, U.S. Pat. No. 4,897,642, issued Jan. 30, 1990, shows a method for monitoring the status of a multiple part vehicle (such as an eighteen wheel truck) and its cargo carrier through the use of satellites and an earth station.
Knickel U.S. Pat. No. 3,568,161, issued Mar. 2, 1971 shows a vehicle locator system which employs a plurality of sensor stations and a central station. Green et al, U.S. Pat. No. 4,791,572 issued Dec. 13, 1988, shows a locating system that uses the LORAN-C system for positioning information. Gray U.S. Pat. No. 4,891,761, issued Jan. 2, 1990, shows a system for updating a digitized map comparing known and unknown intersections in conjunction with a navigational tracking unit.
The units described in the prior art are complex in operation and do not utilize available cellular telephone technology. The present invention overcomes problems of the prior art by providing a non-complex portable hand-held unit that has cross country capability and versatility for use as a regular cellular telephone in conjunction with a precise navigational locating system that can be conveniently and easily carried for transmission and display of position information at a base location.